Two series of copper (I) halide complexes formulated as [(L)CuX(μ2-L)2CuX(L)] and [(L)2Cu(μ2-L)2Cu(L)2]2+ 2χ−, respectively (X = Cl, Br and L = 4,6-dimethylpyrimidine-2-thione (dmpymtH)) were prepared. From the thermogravimetric curves it was found that among the four studied materials, [Cu2(dmpymtH)6]2+2Cl− presents a lower thermal stability. For the determination of the activation energy (E) two different methods have been used comparatively, since every method has its own error. These methods were the isoconversional methods of Ozawa, Flynn and Wall (OFW), and Friedman. The dependence of the E on the value of the mass conversion α, as calculated with OFW and Friedman’s methods, can be separated in three distinct regions. The decomposition mechanism is very complex and can be described using at least three different mechanisms with different activation energies. The best fitting of experimental data with theoretical models gave nth-order for all the three mechanisms (Fn–Fn–Fn).
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